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Full text of "Alaskan glacier studies of the National Geographic Society in the Yakutat Bay, Prince William Sound and lower Copper River regions"

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tered young shrubs that grow there contrast with the older trees of the moraine on either side and with the thick grass of the older, outer, outwash apron.
Baker GlacieróGeneral Description. Baker Glacier is a small, steeply-cascading ice tongue, descending from a level of 5000 to 6000 feet in a series of cirques on the southwestern side of Mt. Muir. It has a total length of less than 2 miles (Fig. 46) and terminates about 1300 to 1500 feet above the level of the fiord. At the terminus the width is 3000 feet. The glacier ends on a very steep slope and a narrow pendant ice tongue with a length of 800 feet and a width of 300 feet extends forward from the terminus, its lower
end being about 700 feet above the fiord. All of the glacier is white, considerably crevassed, and without moraines. Advance. Photographs by the Harri-man Expedition in 1899 and by Grant, Paige, and Higgins in 1905 and 1909 show that, except in one respect, the main features of this glacier have remained unchanged. There was no appreciable change from 1899 to 1905, but a slight advance began between 1905 and 1909, as noted by Grant and Higgins. This advance continued up to 1910, particularly
FIG. 46.
on the north side. Although the form of the glacier front changed very little, the advance was appreciable in photographs.
The Snow Fan. The most conspicuous result of this advance was the increase in discharge of ice from the front of the glacier, which ended on such a steep slope that at the time of our visit blocks of ice were constantly rolling down. In 1905 there was so small a discharge of ice blocks that no accumulation at the cliff base is visible in the 1905 photograph; in 1909 a great snow fan or talus remained until the last of June; in 1910 this was even larger and formed a conspicuous deposit made up of snow and great blocks of ice, some 10 to 15 feet in diameter. When we saw it in July and August, 1910, the accumulation was evidently made up mainly of material that had gathered and remained unmelted during the previous summers, for a large amount of the material between the ice blocks was old snow; but ice blocks were still rolling down and adding to the deposit. This increase in ice block avalanches is clear evidence of an advance, and apparently represents an early stage in the development of a reconstructed glacier; but the deposit